WELSH Secretary Paul Murphy is hoping government whips will rethink plans to ban cabinet ministers from voting with their conscience on changes to abortion laws.

The devout Roman Catholic is one of three senior Labour politicians who face having to resign if they want to defy the party line on controversial fertility and embryo research proposals.

Although Chief Whip Geoff Hoon – the government’s enforcer – will allow the cabinet ministers to abstain, they will not be allowed to vote against the Human Fertilisation and Embryology Bill if they want to keep their jobs.

Last night sources close to the Torfaen MP said: "He is hopeful that a compromise can be reached. It is a matter of conscience for him but he is hopeful an agreement can be reached for a an open vote."

The Bill has proved highly contentious because it would give the go-ahead for the creation of hybrid animal-human embryos for scientific research.

It would also allow lesbian couples to register as joint legal parents of a child born through fertility treatment, removing the need for a father. And it would also allow the first major Parliamentary vote on abortion since 1990.

Although the Bill has cleared the House of Lords a date has still not been set for the second reading because of the controversy it has attracted.

Mr Murphy has voted for reducing the abortion limit in the past but he is also a renowned government loyalist.

Transport Secretary Ruth Kelly and Defence Secretary Des Browne, along with 15 ministers, are also unhappy at the measures being proposed. Tories will get a free vote.

Tory leader David Cameron has given his MPs a free vote on the entire Bill.

Campaign group Alive and Kicking, made up from the Christian Medical Fellowship, ProLife Alliance, the Guild of Catholic Doctors, the Evangelical Alliance, and the Lawyers’ Christian Fellowship, will target individual MPs to put pressure on the vote against the Bill.

A spokesman for Mr Murphy said: "This Bill raises important issues in trying to deal with disease but also ethical issues and we are trying to work through these at the moment